This is not about a product not being profitable, but about an alternative strategy being more profitable, and an open system does indeed discourage choosing the alternative strategy, precisely because it prevents a single actor from being able to withdraw the product from the market.

With email (well, email before people were stupid enough to use gmail), if a single provider withdraws their email offering from the market, that does not really have much of an effect on the system as a whole, the affected users just switch to a different provider and email overall just continues to work as it always did - which in turn should discourage companies from withdrawing their email offerings in favour of their proprietary offerings, as they would expect people to switch to a different provider rather than to their proprietary offering.

Well, in practice, though, people just seem to be too stupid to understand such basic economic realities as network effects and the effects of monopolies/dictatorships/other concentrations of power and what the long-term effects of those are, and so facebook and twitter do actually have users, so something about that theory must be wrong, I guess.

With email it all boils down to owning your email, on your own domain, with Gmail no less, speaking of which people had yahoo.com and hotmail.com accounts long before Gmail. And if you don't own the email address, it's painful to make a switch, though much less painful than switching from FB to something else.

There is a big difference between email and FB - people depend on email on a daily basis, especially for work. When 2 people exchange contacts, what do they exchange? Their phone and email of course. Do you give out your FB or Twitter handle to people?

Email is reliable, everybody has an email address and everybody with an email address can communicate with you. My father doesn't have the patience to be on FB, he can barely use a laptop or his phone, but he does use email.

My point is - these new platforms for communication will never replace email and I also believe that because of the lock in, FB and Twitter and G+ will never be so relied upon as to be irreplaceable. This lock in these bring is also their weakness.

Yeah, the problem with gmail is not gmail itself, but rather its success. If everyone/a majority/too many people use(s) gmail, that puts google into a position where they would be able to change the system unilateraly, that is why I think it's stupid when people, in particular people who should know better, use gmail. Well, plus the fact that google has plenty of motivation to hinder privacy in emails because their business case is built on reading your emails, which makes it all the more scary that they could get into a position to dominate email.

Other than that: Oh, I hope you are right! But don't underestimate network effects - people were also stupid enough to let Microsoft lock them into word documents, which indeed were practically irreplacable for quite a while, and to a degree still are.

I find it reassuring that Google tried to do something similar before, when Google Groups attempted to take over Usenet, and people using real newsgroups had little time for either Google's "replacement" or for people who were accessing Usenet via Google Groups and thought everyone else should/must be as well.

And more recently how Google dealt with XMPP. I certainly would not want to rely on them not breaking email when it's to their advantage.

Not sure what you mean, but Google Groups is basically enabling ... mailing lists. So we go in circles, back to email.

Google groups was based on Google acquiring DejaNews and building a usenet archive and interface on top of that - mailing lists are a later addition. The usenet interface was (and I guess still is?) terribly broken, making it a pain for other usenet users to deal with posts from google groups users, because it simply works in a way that hinders interoperability with the rest of usenet.

(And while at it: The mailing list feature is also quite defective, obviously built by people who don't really have a clue how email works.)

OK, I understand what you're saying. I'm not really familiar with the history of Usenet and Google Groups it seems.

And for mailing lists it could be better, but as a user of several mailing lists of various open-source projects, I have had no problems.

I am noticing that Google doesn't work in our interests though. For example I am disappointed by their shitty support for IMAP, CalDav and CardDav.